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Understanding Which Industrial Diesel Generators Are Ideal for Industrial Use

Which Industrial Diesel Generators Are Ideal for Industrial Use

Presently, industrial diesel generators offer the best backup power solution for most large industrial power users. So, what are industrial diesel generators? A generator is a machine that uses virtually any source of rotational energy to rotate an armature in an alternator to produce electrical energy. Various types of internal combustion engines, fuelled with any of several petroleum-based fossil fuels, are typically found.

Although generators powered by internal combustion engines are the most common units manufactured, steam or the kinetic energy stored in water (hydropower) is also used to provide the rotational energy to drive the alternator. Industrial diesel generators are made up of two primary components, a diesel-powered engine and an alternator and for this reason, are also referred to as gensets.

The rotation of the armature in industrial diesel generators produces an output voltage in three sequential sine waves. Each wave is offset by 120° from the other two which constitutes one full rotation (120° x 3 = 360°). This produces continuous Alternating Current and voltage as long as the engine runs. If the engine runs at a constant speed of 1500 revolutions per minute (RPM), 400 volts of electrical output at a frequency of 50 Hz is produced. By running industrial diesel generators at different RPMs, varying voltage and frequency output can be produced.

Industrial diesel generators are invariably configured to produce three-phase power. Three-phase generators are essentially three single phases contained in one unit, enabling them to produce far more power output than a single-phase unit. Put another way, a three-phase generator has 180% more capacity.

Industrial Diesel Generators Keep Production Going and Minimise Risks

Power outages in the commercial and industrial sectors create uncertainty, cause waste of in-process materials, drive production costs up and may damage plants and machinery. Where grid power is unreliable, industrial producers are exposed to the risk of substantial financial losses. In a developing country, unreliable electricity supply offsets lower labour costs, reducing a potential competitive advantage. Industries affected by constant power outages can’t deliver services or products to their customers consistently, creating the risk that these customers may find alternative suppliers and be lost permanently. Industries with temperature-sensitive production processes or perishable products are most at risk of suffering significant losses. Agricultural operations that rely on irrigation are also exposed to the risk of crop losses or reductions in yield.

While there is an uptake in employing renewable energy systems in the industrial sector, several considerations need to be made when deciding between renewable options and diesel generators. For one, the latter can be deployed rapidly. The capital cost for these units will be substantially lower than a renewable energy solution of similar capacity. Renewables suffer from intermittency (the sun doesn’t shine at night), and industrial-scale battery storage demands a significant upfront capital investment. Renewable solutions do not have the rotational torque of a genset, so they suffer from low systemic inertia and may struggle to start and run heavy industrial loads and large electric motors. While industrial diesel generators need more maintenance and burning diesel is relatively expensive, on a balance of considerations, they remain the most attractive option.

Types of Industrial Generators

Several types of generators suitable for the industrial sector are outlined below:

1. Diesel-powered Generators

Diesel-powered generators dominate the market for industrial generators. Diesel engines are renowned for their durability, long service life and relatively low maintenance costs. A diesel engine operating at 1500 rpm can run for up to 30,000 hours before needing a major service.

Diesel burns cooler than petrol reducing the heat stress, and, consequently, the wear on the engine. Modern industrial diesel generators are extremely efficient in exploiting the high energy of diesel fuel. Improvements in diesel engine technology have also cleaned up diesel engine exhaust emissions reducing their environmental impact.

2. Gas-powered Gensets

Gas-powered gensets, that use propane or liquefied petroleum gas (LPG), are also available. Natural gas and LPG are easy to store in below- or above-ground tanks and both are clean burning fuels, reducing environmentally harmful emissions. Gas-powered gensets are typically more expensive to purchase and will have lower power output than a similar-sized diesel generator. Piped gas may be less expensive than other fuels but if it must be trucked to your facility the cost-benefit is lost.

3. Petrol-powered Generators

Petrol-powered generators are rarely used for large capacity gensets although they are usually cheaper size for size. They require more frequent maintenance and petrol is damaging to certain engine components such as those made from rubber. Because petrol is more volatile than diesel, fuel storage is more difficult as petrol has a higher potential for fire or explosions. Stored petrol deteriorates more rapidly than diesel making long-term storage problematic. They are also not as good as diesel for larger industrial applications and manufacturers consequently do not produce large-capacity petrol-powered gensets.

4. Heavy Fuel Oil-powered Units

Heavy fuel oil-powered generators offer significant fuel savings over diesel-powered units. They are also suited to very long continuous operation, have a long life expectancy, and produce less noise. They are best in very large-capacity applications such as industrial facilities, mining enterprises, regional power plants and large ships. They are not portable, and the initial cost of procurement and installation is high.

The ready availability of heavy fuel oil must be considered when selecting this type of generator as heavy-fuel oil is not as ubiquitous as diesel is.

Choosing the Correct Capacity Industrial Diesel Generators

When sizing industrial diesel generators, you need to consider the total power requirement as well as the type of equipment that will be operated. Industrial plants with multiple electric motors or compressors need careful sizing and it can be a complex electrical engineering challenge. It’s a misconception that the genset can simply be made far larger than required. Simply buying the biggest genset you can afford is not a ‘safe’ option.

Industrial diesel generators that are too large for the application use far more diesel than necessary, and the capital cost will be higher than that of a smaller unit. The real issue, however, is the fact that gensets should ideally be run at around 75% of their maximum capacity for optimum performance and longevity. This allows them to run in the correct thermal range which increases their life span, cuts down on maintenance and burns less diesel. Running industrial diesel generators at less than 30% of their capacity for extended periods is inefficient and will often cause expensive damage to the engine.

Track Record is Everything

Industrial-scale power generation is a specialist field, and it is crucial to engage with the correct partner. PacB Power Solutions has a long history of providing service and technical excellence and is an industry leader in the power generation industry in Southern Africa. We provide leading engine brands and alternators with top-quality ancillary components.

Larger-capacity industrial diesel generators require experienced engineers and technicians to design and implement optimally. Choosing an unsuitable unit will carry severe financial and operational consequences. Choose PacB for your power system. We have an unimpeachable track record and are experts in the integration of diesel generators and renewable energy sources. Engage with us to learn more.